Marie, 31, also revealed that her great aunt also passed away in December, only weeks after she filed for divorce from husband Mike Shay, 29.
Shay has not yet publicly responded to Marie's sad news, and they have not spoken since the explosive Vanderpump Rules reunion taping.
Valletta and Marie began dating shortly after she announced her split, and they even spent the holidays together.
They have recently gone public with their relationship, but it is unclear if Valletta will appear on season six of the hit Bravo show.
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